Methods and compositions relating to useful antigens of moraxella catarrhalis

Abstract

The present disclosure relates to selected antigenic proteins obtained from the outer membranes of Moraxella catarrhalis, that have been found by the inventors to have a variety of useful properties. These proteins, termed OMPs ("Outer Membrane Proteins"), are characterized as having molecular weights of 30, 80 and 100 kD, respectively. Studies set forth herein demonstrate that monoclonal antibodies directed against these proteins confer a protective effect against infection by Moraxella catarrhalis organisms in animal models, demonstrating the potential usefulness of such antibodies in conferring passive immunity as well as the potential usefulness of these OMPs, or variants thereof, in the preparation of vaccines. Also disclosed are DNA segments encoding these OMPs, methods for preparing the antigens, or variants, through the application of recombinant DNA techniques, as well as diagnostic methods and embodiments.

What is claimed is: 
     
       1. A process for preparing an antigen composition, comprising the steps of: (a) selecting cells expressing a Moraxella catarrhalis outer membrane protein or peptide antigen having an epitope that binds to a monoclonal antibody selected from the group consisting of 8B6 (ATCC HB 11091), 10F3 (ATCC HB 11092) and 17C7 (ATCC HB 11093);   (b) culturing said selected cells under conditions effective for expression of the antigen; and   (c) collecting the antigen to prepare the composition.   
     
     
       2. The process of claim 1, wherein the antigen comprises an M. Catarrhalis outer membrane antigen of about 30, 80 or 100 kD as determined by SDS-PAGE. 
     
     
       3. The process of claim 2, wherein the cells comprise M. catarrhalis cells. 
     
     
       4. The process of claim 2, wherein the cells comprise recombinant host cells that express a recombinant DNA segment encoding the antigen. 
     
     
       5. The process of claim 4, wherein the recombinant host cells comprise bacterial host cells. 
     
     
       6. The process of claim 5, wherein the bacterial host cells comprise E. coli, H. influenzae, Salmonella, Mycobacterium, or Bacillus subtilis cells. 
     
     
       7. The process of claim 4, wherein the recombinant DNA segment encodes an M. catarrhalis antigen that binds to a monoclonal antibody selected from the group consisting of 8B6 (ATCC HB 11091), 10F3 (ATCC HB 11092)and 17C7 (ATCC HB 11093). 
     
     
       8. The process of claim 1, further comprising purifying the antigen by a method that includes detergent extraction of outer membrane vesicles of M. catarrhalis. 
     
     
       9. The process of claim 1, wherein the antigen binds to the monoclonal antibody 8B6 (ATCC HB 11091). 
     
     
       10. The process of claim 1, wherein the antigen binds to the monoclonal antibody 10F3 (ATCC HB 10092). 
     
     
       11. The process of claim 1, wherein the antigen binds to the monoclonal antibody 17C7 (ATCC HB 11093). 
     
     
       12. The process of claim 1, wherein the antigen is purified to be essentially free from M. catarrhalis antigens other than those that bind to the monoclonal antibody selected from the group consisting of 8B6 (ATCC HB 11091), 10F3 (ATCC HB 11092) and 17C7 (ATCC HB 11093).